This application is a resubmission for continuation of a Training Program in the Molecular Biology of Cancer, which is in its 25th year of operation and is an integral component of the NCI Clinical Cancer Center (P30 CA44579) at the University of Virginia Health System. Training is conducted at the predoctoral level leading to the Ph.D. degree, as well as at the postdoctoral level, for those who already hold the Ph.D. or M.D. degree. Cancer-relevant, in-depth training opportunities are a v ailable in the areas of genetics, molecular and cellular biology, biochemistry, membrane structure and function, structural biology, viral and bacterial oncology, immunology, signal transduction, development and differentiation, and drug discovery. Both pre- and postdoctoral trainees are provided a broad perspective in cancer research through programmatic activities, such as a formal course on the Molecular Basis of Cancer (MBC), Cancer Center seminars, a state-wide cancer symposium, clinical workshops, and encounters with cancer patients. For predoctoral students, training is based on a Core Curriculum, which is augmented by specialized courses (particularly MBC), seminars, symposia, journal clubs, teaching experiences, participation in national and state meetings, and completion of an independent research project. Postdoctoral training emphasizes laboratory research and participation as faculty and/or student in the MBC course and other programmatic activities. Ph.D. degrees or postdoctoral training can be obtained from any of the participating departments or degree-granting programs, including Microbiology, Biochemistry, Pharmacology, Physiology, Cell Biology, Biophysics, and Neuroscience. Research mentors are drawn from the faculty of these Departments and Programs, with emphasis on those individuals who are involved in cancer-related research. Predoctoral candidates for the Ph.D. degree are selected from among students applying directly to the Microbiology Ph.D. program or any other of the component degree-granting programs and designating an interest in cancer research on their application form, from those applying for admission to interdisciplinary programs (such as Cell and Molecular Biology, Molecular Medicine, and Medical Scientist Training Programs), and from those who are receiving research training in the laboratories of the Training Faculty, regardless of department. Postdoctoral trainees are selected from a pool of eligible candidates who are already studying with faculty mentors of the training grant. Pre- and postdoctoral candidates are admitted on the basis of academic achievement, cancer-related interests, letters of recommendation, research experience, motivation, and GRE scores. Based on the high percentage of past trainees (both pre- and postdoctoral) who have chosen careers in cancer research, support for 15 Ph.D. candidates and 3 postdoctoral trainees is requested in the first year. The facilities available for this training are state-of-the-art and are supported by a plethora of Core Laboratories. The goal of the Program is to prepare selected individuals for careers in teaching and basic research relevant to problems in cancer biology.